The invention concerns a mass balancing mechanism for compensating mass forces and/or mass moments of inertia of an internal combustion engine. The mass balancing mechanism comprises a compensation shaft comprising a tubular carrier shaft comprising a mounting point configured on the outer periphery of the carrier for radial mounting of the compensation shaft in the internal combustion engine, and the mass balancing mechanism further comprising an unbalanced mass which is connected to the carrier shaft and joined to the carrier shaft on a connecting section of the carrier shaft extending laterally of the mounting point.
A mass balancing mechanism of the above-noted type is disclosed in an article “Der neue 1,8-I-Vierzylinder-Ottomotor von Mercedes-Benz” published in the Motortechnische Zeitschrift (MTZ), Issue of June 2009. The mass balancing mechanism comprises two compensation shafts rotating in opposed directions at double the speed of rotation of the crankshaft and serving to compensate free mass forces of the second order. These shafts are constructed as compensation shafts which comprise a tubular carrier shaft and are pushed into a mounting channel of the internal combustion engine and then screwed to two respective unbalanced masses.
The radial mounting of each of the compensation shafts is effected at three sliding bearing locations. It is well known that sliding bearing-mountings produce clearly higher friction work losses than rolling bearing-mountings, so that rolling bearing-mounted compensation shafts are being increasingly used in large series production. In addition, the pressure medium supply which is obligatory in hydrodynamic sliding bearings can be omitted, because, typically, the lubrication of rolling bearing-mountings is realized solely through the oil mist formed during operation, as has been proposed in EP 1 775 484 A2.